Why should economists continue to work on such ambitious Big Ideas in Development -- what drives Development? Freedom? Property Rights? Human Capital? Whether you are just like ME?
One good reason is that most people are going to have their own Big Ideas anyway. If economists and other social scientists refuse to discuss Big Ideas, then people will just base them on some random anecdote or on laughably casual empirics. (I once heard a prominent non-development economist say he understood underdevelopment after his first 5 minutes in a poor country.)

One way that casual back-of-the-envelope empirics seems to work is I judge other peoples more favorably the more they are like me.

One of the worst forms of Me-ism is racism. What could be more direct than just assume the rich people are racially superior to the poor people? Racism was the prevailing explanation in "Development Economics" for 5 centuries until racism became politically unacceptable (and was refuted scientifically).

Racism (like other forms of Me-ism) is just lazy empirical work. You go for some superficial correlate of development that has no other evidence behind it --other than your instinct that everybody should be judged by how similar they are to you.

So thank goodness that many development economists are continuing to write about all the above topics. They may not achieve 100% airtight evidence, they may not definitively resolve what causes what, but I think they do better than the Me-ists and the racists who decide the answer in the first 5 minutes.